Roller boring-drill.



H. R. HUGHES.

ROLLER BORING DRILL.

PPLIGATION IILBD J NE 20,1913.

Patented D00. 1, 1914.

2 s Mfrs-SHEET 1.

HOWARD B. HUGHES, OF HOUSTON, TEXAS.

ROLLER BORING-DRILL.

Specication of Letters Patent.

Patented Dec. 1, 1914.

Application led June 20, 1913. Serial No. 774,778.

To all whom it may concern Be it known that I, HOWARD R. HUGHES, acitizen of the United States, residing at Houston, Texas, have inventeda certain new and useful Improvement in Roller Boring- Drills, of whichthe following is a full, clear, and exact description, such as willenable others skilled in the art to which it appertains to make and usethe same.

This invention relates to roller boring drills.

One object of my invention is to provide a strong and rigid rollerboring drill that can be manufactured at a low cost, and which is sodesigned that sufficient clearance is always provided around the drillhead to permit the displacements and cuttings to get by the drill andthus enable the drill to reach the bottom of the hole.

Another object is to provide a roller boring` drill in which the cuttingrollers are so arranged that the head of the drill will remain centeredin the hole and consequently will not wabble from side to side duringthe drilling operation. And still another object is to provide a rollerboring drill in which the rollers are so arranged that the head can beprovided with bearings for both ends of the spindles on which thecutting rollers are mounted.

Other objects and desirable features of my invention will be hereinafterpointed out.

Figure 1 of the drawings -is a vertical sectional view of a rollerboring drill constructed in accordance with my invention; Fig. 2 is abottom plan view of said drill; Fig. 3 is a vertical sectional viewtaken at approximately right angles to Fig. 1; and Fig. 4 is a bottom vplan view illustrating a slight modification of my invention.

Referring to Figs. 1 to 3 of the drawings which illustrate the preferredform of my invention, A designates the head of the dri\ll which ispreferably formed in one piece an provided at its upper end with ascrewthreaded boss 1 to which the hollow drill stem or operating member,not shown, is connected. A ring-shaped flange 2 is also provided at theupper end of the head so as to support a lubricant-holder, notshown.l

Two approximately frusto-conical-shaped cutting rollers B are arrangeddiametrically opposite each other on spindles 3 that ineline downwardlyand inwardly toward the longitudinal' axis of the head A, and two groupsof cutting rollers C and D are arranged intermediate the rollers B onspindles 4 that are arranged at right angles to the spindles 3 andextend transversely across the head A of the drill, the spindles 4 beinginclined in an opposite direction to the spindles 3, or, in other words,being in ined downwardly and outwardly from the longitudinal axis of thedrill head. The inner ends of the spindles 3 are supported by centerbearings 5 on the drill head that lie between the inner ends of therollers B and the inner rollers of ,the groups of small rollers C and D,and the outer ends of the spindles 3 are supported by side bearings 5 onthe head, as shown in Fig. 3. A center bearing 6 on the head, whichextends transversely between the bearings 5 and is preferably formedintegral with said bearings 5, supports the inner ends of the spindles4, and the outer ends of said spindles 4 are supported by integral sidebearings 7 on the head A, as shown in Fig. 1. By forming the drill inthis manner I obtain a very strong and rigid construction in view of thefact that the spindles for the cutting rollers of the drill aresupported at both ends by integral bearings on the head of the drill,and the bearings 5 for the inner ends of the spindles 3 are tiedtogether bv an integral portion 6 of the drill head that supports theinner ends of the spindles 4. The approximately frusto-conical-shapedrollers B are provided at their outer ends with cutting teeth 8 thatshear off the material at the sides of the hole and thus form suflicientclearance for the head of the drill to prevent it` from sticking in thehole, and, if desired, one of said rollers can be larger than the otherso as to allow for wear on the teeth 8 and thus insure suilcientclearance for the head of the drill after the rollers B have becomeworn. In Fig. 4 I have illustrated a drill in which the roller B at oneside of the head is of greater diameter than the roller B at theopposite side of the head so that it will project.. farther laterallyfrom the head and thus describe a circular path of greater diameter thanthat described by the roller B, as indicated in broken lines in Fig. 4.By forming the drill in this manner, namely, equipping it with a rollerthat projects laterally farther from one side of the center axis of thedrill head than the other lot cutting rollers, suilcient clearance forthe 1 drillis insured to reduce the liability of the drill sticking inthe hole to a The rollers C and D are comparatively small rollers andare substantially diskshaped or, in other words, have cutting surfacesthat extend parallel to the axis about which said rollers rotate. Byarranging the rollers C and D on spindles that incline downwardly andoutwardly from a center bearing on the head I obtain a drill in whichthe cutting rollers are so disposed that there is little tendency forthe drill head to wabble owing to the fact that the rollers C and D forma hole whose bottom is substantially pyramidal-shape at the center. Thehead A is provided with the usual water-holes 9 so as to cause jets ofwater to be projected downwardly onto the material displaced by thecutting rollers, and a lubricating duct 10 is formed in the head, asshown in Figs. 1 and 3, for supplying a lubricating medium to ducts 11that lead to the bearing surfaces on which the rollers B rotate and alsoto ducts 12 in the spindles 4 which are provided with branches 12a thatlead to the surfaces on which the rollers C and D rotate. The spindles 3and 4 can be secured to the head in various ways, the means herein shownconsisting of set-screws 13 that are screwed into coperating recesses inthe spindles and in the bearings that support the outer ends of thespindles. Vertically disposed notches 14 are formed in the head atpoints between the bearings 5 and the bearings 7, as shown in Fig. 2, soas to permit the displacements and cuttings to get by the drill head andthus enable the drill to reach the bottom of the hole, the head of thedrill being substantially cruciform-shape in cross section.

A drill of the construction above-described can be manufactured at a lowcost; it is exeeptionally strong and rigid owing to the fact that thespindles for all of the cutting rollers are supported at both ends inbearings on the head; and the center bearings which support the innerends of said spindles are integrally connected to each other and to thehead. The head is so designed that ample clearance around the head isprovided for the material that is displaced and disintegrated by thecutting rollers, thus eliminating the possibility of the disintegratedmaterial packing in the hole; and still another desirable feature ofsuch a drill is that it will remain centered in the hole andl will not`wabble from side to side duringlthe drilling operation.

aving thus described my inventlon, what I claim as new and desire tosecure by Letters Patent is:

1. A roller borin drill comprising a head provided with inclined sidecutting rollers, cutting rollers arranged transversely of the headintermediate said side cuttin rollers, spindles for said intermediaterol ers that incline downwardly in opposite directions from thelongitudinal axis of the head, and

.a pair of bearings on the head for supporting both ends of saidspindles.

2. A roller bearing Y drill comprising a head provided with a centerbearing and with slde bearings oppositely inclined, spindles supported1n said bearings and provided with cutting rollers, and a side cuttingroller on said head whose axis of rotation is disposed at approximatelyright angles to said spindles and inclined downwardly from the outerside toward the center of the head.

3. A roller boring drill comprising a head provided with side bearingsand with a center bearing that is located at the longitudinal center ofthe head, spindles supported at their opposite ends by said bearings andextending transversely of the head, the outer ends of said spindlesbeing inclined downwardly, cutting rollers on said spindles which form acircular hole in which no center core is left standing, and an independent cutting roller on said head arranged to travel in the circularpath described by the side bearings of the head when the head isrotated.

4. A roller boring drill comprising a head provided with a centerbearing and with side bearings transversely disposed, spindles supportedby said bearings and having their outer ends inclined downwardly,cutting rollers on said spindles that disintegrate the material at thecenter of the hole, and an approximately frusto-conical-shaped cuttingroller on the head whose axis is inclined inwardly and downwardly towardthe longitudinal center of the head and whose function is to cut acircular ath through which said side bearings trave 5. A roller boringdrill comprising a head, a pair of approximately frusto-conicalshapedcutting rollers arranged diametrically opposite each other on splndlesthat incline inwardly and downwardly toward the longitudinal axis of thehead, and independent cutting rollers arranged intermediate saidapproximately frusto conical shaped rollers on spindles that areinclined downwardly and outwardly from the center of the head.

6. A roller boring drill comprising ahead,

approximately frusto conicalshaped cutting rollers arrangeddiametrically opposite each other on spindles that incline inwardly anddownwardl toward the longitudinal axis of the head, lndependent cuttingrollers arranged intermediate said approximately frusto-conical-sha edrollers at right angles 'thereto on spin les whose outer ends areinclined downwardly, and bearings on the head for supporting both endsof all of said spindles.

7. A roller boring drill comprisingahead provided with a group ofoppositely 1nclined rollers that extend transversely Vof the head andwhich are so arranged that they will form an approximatelypyramidalshaped surface at the bottom of the hole, and a pair ofapproximately frusto-conicalshaped rollersarranged diametricallyopposite each other on opposite sides of said group of rollers onspindles that incline downwardly and inwardly toward the longitudinalcenter of the head.

8. A roller boring drill comprisingahead, approximatelyrusto-conical-shaped cutting rollers arranged on inclined spindles whoseopposite ends are supported in the head, and a pair of oppositelyinclined spindles arranged transversely of the head between saidfrusto-conical-shaped rollers and provided with cutting rollers thatremove the material at the center of the hole.

9. A roller boring drill comprising a head provided with a palr ofcenter bearings that are spaced apart and side bearings that cooperatewith said center bearings oppositely inclined,vspindles supported attheir opposite ends by said bearings and provided with approximatelyfrusto-conical-shaped cutting rollers, and two groups of oppositelyinclined cutting rollers arranged transversely of the head intermediatesaid approximately frusto-conical-shaped rollers and extending atapproximately right angles to same.

10. A roller boring drill comprising a head provided with a pair ofspaced center bearings and with side bearings that coperate with saidcenter bearings, inclined spindles supported by said bearings andprovided with tapered cutting rollers that are arranged diametricallyopposite each other, a spindle-supporting means formed integral withsaid center bearings and acting to tie same together, and oppositelyinclined spindles supported at their inner ends by saidspindle-supporting means and provided with cutting rollers.

11. A roller boring drill comprising a head provided with a centralspindle-supporting means, four spindles supported at their inner` endsby said means and projecting radially therefrom, bearings on the headfor supporting the outer ends of said spmdles, and cutting rollers onsaid spindles, said spindles being arranged in pairs with thecooperating spindles of each pair inclined in opposite directions.

12. A roller boring drill comprising a. head provided with a centralspindle-supporting means, a pair of approximately ,frusto-conical-shapedcuttin rollers mounted on short spindles that incline downwardly andinwardly toward the longitudinal axis of the head, the inner ends ofsaid spindles being supported by said means, and a separate and distinctpair of oppositely inclined spindles supported by said means andprovided with cutting lrollers that disintegrate the material at thecenter of the hole.

13. A roller boring drill comprising a head of approximatelycruciform-shape in cross section provided with a centralspinolle-supporting means, pairs of oppositely inclined spindlesarranged at ri ht angles to each other and branching radially from saidcentral supporting means, bearings on the head for the outer ends ofsaid spindles, and cutting rollers mounted on said spindles.

In testimony whereof I hereunto affix my signature in the presence oftwo witnesses,

Ithis eleventh day of June, 1913.

HOWARD R. HUGHES.

Witnesses HYMAN LEvIN, EARL LEIB.

